Tumblr and Pinterest have younger users.
70% of users are between 16 years and 34 years.
While Facebook has a more adult audience, with over 25% of subscribers / users over 45 years.

As for the app, used on mobile, from smartphones and tablet:
1) Snapchat (growing by + 56%)
2) Facebook (it has a 43% stake)
3) Facebook Messenger (it has a 27% market share)
4) WhatsApp (it has a 25% share) (WhatsApp is owned by Facebook)